Table 3: Proposed Detached Two-Family "House Type" Assignments and Resulting Change in Nonconformity as of 11/1/20
Approximately 10% of Newton's Two-Family Homes are side-by-side units with separate entrances, termed "Family Duplex" by the Assessors. This construction is no longer  specified  by the Planning Department as a two-family, but (possibly) as a "Townhouse Section" that is only allowed in the new N district. is calling this type  "NoSpec:FD,"  and giving it an allowed footprint of 2 X the townhouse section footprint in the nonconformity analysis. Traditional Two-Families have been defined as a "Duplex" Type by Planning, "with one unit above and one below, or the second floor is split between the two units as in the case of a 'Philadelphia-style' duplex."
House Type Assignment [1] Duplex
[Two Vertical Units]
[Two Side-by-Side Units]
All Two-Families
Story Number Limit for House Type 2.5 3 Assumed  
Footprint Limit for House Type in sq. ft. 1,800 3,000 Assumed
2 Townhouse sections
Districts where House Type is allowed by right R3,R4,N N Assumed
Number of Homes in R1,R2 297 23 320
Number of Homes in R3,R4,N 1,989 254 2,243
Total Number of Homes 2,286 277 2,563
Ave Lot Size Sq. Ft. 8,304 9,097 8,389
Ave  Living Area Size Sq. Ft. 2,809 2,766 2,804
% Homes nonconforming with CURRENT side/rear setbacks 64.0% 56.0% 63.1%
% Homes nonconforming with PROPOSED Side/Rear Setbacks 80.3% 74.0% 79.6%
% Homes nonconforming with footprint and story height limit defined by house type 36.7% 0.7% 32.9%
% Homes nonconforming for being outside allowed district for House Type [2] 13.0% 97.8% 22.2%
% Homes nonconforming with PROPOSED story height, footprint, district, and side/ rear setbacks. 89.7% 98.2% 90.6%
 Data Exclusions: Estimate of Two-Family Houses = 2,722. Data was excluded if houses were not in a Residential District in current and proposed zoning. This eliminated 159 houses, leaving a sample size of 2,563 two-family family homes.
[1] Zoning Specs. from 8/7/20 Planning Department memo. Sasaki Measurements and proposed districts from 2019 Build-Out Analysis.
[2] This analysis assumes that all "NoSPEC:FD" [Side-by-side two-familys] are now zoned as two townhouse sections where each townhouse section has an allowed footprint of 1,500 sq. ft.